Boolean modifier just remove my object
I turns out that I just need to click on &quot;self&quot; on the modifer, no idea why it's not checked by default:

EDIT: as pointed out in the comment, the problem may be instead that the shape had double vertices (created when I turned the cylinder into a cone by scaling one side). Therefore, it may also be enough to remove doubles vertices (Edit mode &gt; Mesh &gt; Merge &gt; By distance), thanks!